Casting machine



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S. J. SYMMONS CASTING MACHINE 1922 2 sheets-shew l Filed July 21,

INVENTOR 6* Jy/Vwm mw j Y. i

am ATTORNEY MMA-27, 1923.

s. J. sYMMoNs CASTING MACHINE Filed July 2l,

192.2 2 sheets-sheet 2 INVENToR.

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Patented liliana 2?, 1923.

Ulli? SAMUEL J. SYMIVIONS, OF SAN FRANCISCO, CALIFORNIA.

CASTING MACHINE.

Application ied July 21,

To LZ2 ywhom 'it may concern Be it known that LSAMUEL JAMES SYM- Mozvs, a citizen of the United States, residing at 2l() Stockton Street, in the city oit' San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements ina Casting Machine, of which the following is a specification.

This invention relates to metal casting machines and particularly to machines of the class known as compressed air casting machines designed to be used especially by dentists in the casting of inlays, saddles, full and partial plates, and bridges, and sa-id machines may be used by jewelers and others in the casting ot small `or comparatively small metallic parts.

It is customary to form such castings in a mold cavity formed in a body ot investment material contained in a fiask. the metal being melted on the top surface of the investment and taused, partly by suction and partly by pressure, to accurately till the mold.

Difficulty has been experienced heretofore in the use of dental casting'machines by which metallic inlays for teeth are formed, owing to the multiplicity of operations necessary during the process of molding the inlay or other article as the case may be.

The object of the. invention is to provide a casting machine wherein the number of operations` necessary on part ot the person making the mold and casting the inlay is reduced to a minimum so that the successful production of a casting is assured with a high degree ot eiiiciency.

The invention is fully disclosed in the following specification. of which the accompanying drawings Jr'orm a part` in which the separate parts of my improvement are designated by suitable reference characters in each of the views. and in which Figure 1 is a sectional view of my improved machine indicating the parts thereof in a normal position;

Fig. 2 is a side elevation of the machine showing the operative mechanism. parts of the machine being omitted;

Fig. 3 is a top plan view of the flask supporting plate:

Fig. 4 illustrates a sectional view of the Flask closing head for forming the matrice.

The machine illustrated in the drawings comprises a suitable supporting base or 1922. Serial No. 576,530.

foundation 1, carrying the stationary part of 'the machine, and which may rest upon a table or other support. (.)n said base are mounted a flask supporting plate 2 and a vertically mounted cylinder 3, supported on the base 1 by an annular raised stand 4 securely attached to the base 1.`

The flask support for the machine comprises a plate 5 mounted on tour telescoping stems 6 sliding into four hollow standards 7 rising from the base 1. Surrounding each stem is a spiral spring 8 whose upper extremity bears against the plate 5, the lower extremity of the spiral spring engaging a shoulder 9 formed on the standards 7. The spiral springs thus positioned places the stems G. together with the plate 5 supported thereby, under tension to move upwardly and permit ot' a limited rocking movement of the plate to automatically adjust itself when depressed into position by the flask as will presently be explained. (()nly tWoof the said stems and standards being shown on i the drawing.) A flask 10 is shown on Fig. 1.` in operative position upon the plate 5. 'lhe centialportion ot the plate 5 being perforated as at 11 to facilitate a pre-heating of the flask by any suitable means. here not shown. The plate 5 is'reduced at one end as at 12 and threaded therein is an adliustable releasing stem 13 having a formed head 11 at its upper end. This releasing stem is designed to be manually raised or lowered. to retard or to accelerate respectively the. release of the pawl .29 as will presently be explained.

rlhe upper end of the c vlindcr 3 receives threaded thereon a cover 15 provided with an air valve 1G. a pressure gage 1T and a flexible conduit 1S. Arranged to operate within the said cylinder is a piston 19 having secured thereto and extending downwardly therefrom a metallic piston-band 20 slidable longitudinally through a collar .21 secured into the lower part .of the cylinder. Surrounding the said piston-band within the said cylinder are two grouped or nested compression springs 22 and .222 the outer and inner coils otl which are made with a different direction of helix to prevent binding of the same. The said spring having bearing at one end against the piston i9 and at'its other end against the collar Q1, and the inner spring QQ having bearing at its upper cad within the piston skirt and at its lower end against said collar 21. The

suitable e object sought istol increase the carrying capacity within the given cylinder space. The said springs norinally holding the piston in aV raised position, while the lowei` end of the piston-band Q is attached to ay i'evolving drum 23 Secured to the shaft 2a journaled in suitable bearing ears formed on the cylinder 3. latching wheel 26 having an operating lever QT is secured on the outer end of shaft Q4: for the purpose of turning said drum 23, winding the meta-llic band 2O around the same and thus depressing the piston 19 to an operative position. 'Means are provided for locking the piston in this depressed position against the stress of the springs 22 and 2Q within the cylinder 3, and for this purpose a ratchet Y wheel 28 is secured to the opposite eiid of the shaft 24 acting in unison with the latching wheel 26. A pawl 29, pivoted to a rearwardly extending bar 30, pivotally mounted on a standard 31 to the base 1, held normally in position by means of a tension spring 32, engages the notches on the ratchet wheel Q8 ,to preventl return motion.' To maintain the pawl 29 in proper cooperative relation to `the ratchet wheel 28, a small coil spring means is provided as at 32, and with this construction the drum Q3 will be locked against the tension of the coil springs Q2 and 22 within the cylinder 3, until released.

Ar carrier 33. which is movable in a path parallel with the axis of the cylinder 3, is preferably a tube 31 slidably mounted in a suitable guide 35 on the cylinder structure. To the lower end of the tube 3-1 is secured an outwardly flared cap 36 of such a` size as to conforml to the size of the flask 1l). De-

itachably applied to the lower surface of the cap 36 is a disk 36 composed of asbestos or other suitable material adapted to seal the top of the iiask 10. Surrounding the tube 34 and interposed between the guide arm and the plate 37, is a coiled spring 39, normally urging the carrier to a raised or inoperative position as shown on Fig. 1.

It should be explained that the flask supporting plate of the struct-ure is mounted to have a limited rocking movement to allow the ask 10 to automatically .adjust itself when depressed by the sealing cap 36 during the time of operation.

To the upper end of the tube 34 is secured a cover plate 37 connecting with the flexible conduit 18. A suitable operating handle is carried by the plate 37 as shown at 38, whose outer surface is milled or roughened to facilitate manipulation.

The method of employing the machine hereinbefore described will largely be un der-stood from the description already pre- Y sented. T'heniethod of forming the matrice in the flask need not fj'ecifically be referred to since the same is. well understood in the art. When the matrice has been formed. the

, cation.

flask 1() is ready to be placed on the plate 5 as shown on Fig. 1. and the globule of metal placed on the surface of the matricel in a pocket provided therefor, as' usual. and fused by means of a blowpipe or other means so that the fused metal may flow down wardly through ay gate into the mold. Just as this operation is about to take place, the carrier 33 is depressed by means of the manually operated handle 38, the cap 36 by virtue of itsy connections as heretofore described, will be forced into sealing relation with the upper edge of the flask 10, before the carrier reaches the downward limit of its movement. Thisr downward pressure of the carrier has also lowered the flask and its supporting plate 5 including the releasing stem 13, adjustably secured to said plate. thus depressing the bar 30 and suddenly releasing the pawl 29, the piston 19 within-the cylinder 3 is set free to the tension of the coil springs 22 and 22a driving the said piston upward and forcing the air within the cylinder, by means of the flexible tube 31 into the flask 10 and upon the fused metal. This sudden release is important for the reason that a strong air pressure effect is exerted immediately upon the matrice and the fused metal Hows instantly thereinto without possibility of premature solidifi- The preliminary operations necessary for using' this machine may be performed beforehand that is` the release stem 13 ad-r the porous material of" the' matrice and insure an easy' flow thereinto of the molten or fused metal of which the casting is to be made.

The cylinder 3 is of relatively large eapacity, so that only one stroke of the piston therein is necessary to create a sufficient pressure for `one casting operation, thus obviating the continuous pumping operations as in the case of pumps or other means used heretofore.

I am aware that various details of construction may be varied through ay wide range without departing from the princi ples of this invention, and I therefore do not purpose limiting the patent granted otherwise than necessitated by the prior art.

hat I claim as my invention and desire to secure by Letters-Patent is:

1. A casting machine comprising a base, a cylinder mounted on said base, a cover for said cylinder, an outlet in said cover, a flexible conduit connected to said outlet, a guide arm carried by said cylinder, a tube slidably 1 'eric I lll mounted in said guide arm and connected to said flexible conduit. acover on said tube, an operating handle secured to said cover, said `tnbe having a flared lower end to form a sealing cap. a flask. a self-adjustable support therefor mounted on said base, a collar within said cylinder. a winding drum. a piston fitting said c vliiider and having a pistonhand extending through said collar to lsaid drinn. a coiled spring interposed between said piston and said 4collar and adapted when under tension and unrestrained to move said piston in an upward direction. locking means to secure said piston and pistoinbaud in opposition to the f'orce of said spring. said piston and piston-baiid when manually moved downward in said cylinder serving to place said spring under tension and said piston when released. so as tomove under the action of said spring serving to force air through said flexible conduit and tube into the said flask.

2. In a casting machine comprising a base. a cylinder mounted on said base. a cover for said cylinder. an outlet in said cover. a flexible conduit connected to said outlet. a guide arm carried by said cylinder, a tube slidably mounted in said guide arm and coniiected to said flexible conduit. a cover on said tube. an operating handle secured to said cover. a coiled spring interposed between said covei' and said guide arm surrounding said tube. said tube having a flared lower end forming a scaling cap. a flask. a support for said flask mounted on said base colnprising a plate secured on telescopiiig standards. coiled springs interposed between said plate and the loweli parts of' the said standards normally urging said plate upwardly. an adjustable releasing means carried by said plate. said operating handle when manually moved downward in said guide serving to place the sealing cap upon said flask and actuating the releasing means, a. collar within said cylinder` a winding drinn. a piston fitting said cylinder andihaving a metallic piston-hand extending through said collar to said drum. a coiled spring in-v terposed hetwecii said piston and said collar and adapted when under tension and unrestrained to move said piston in an upward direction. said piston andv piston-band when manually moved downward in the said cylinder serving to'pla said spring under teny sion. locking means to secure said piston and piston-band in opposition to the force of said spring. and said piston when released so as to move under the action of said spring serving to torceV air through saidflexible lconduit and said tube into said flask.

Cl. casting machine comprising a base. a cylinder mounted on said base. cover on said cylinder having a flexible conduit. a hollow carrier inovably supported by said cylinderand connected to said conduit. a sealing cap on said carrier. a flask "supported on said base. said cap being adapted to seal said flask. a piston operating in said c vliiidei'. a plurality of compression means within said vcylinder adapted when under tension to inove lsaid piston upward, locking meansl to secure said piston in opposition to the. force ot' said compression means and means for operating said piston to force air from the cylinder into the. flask.

4. In a casting machine comprising a base, a cylinder.mounted on said base. a cover for said cylinder. an outlet in said cover, a flexible conduit connected to said outlet, a. guide aim carried by said cylinder. a tube slidably mounted in said guide arm and connected to said flexible conduit. a cover on said tube, an operating handle secured to said cover, a coiled spring interposed between said cover and said guide arm surrounding said tube, said tube having a flared lower end forming a sealing cap. al flask. a support for said flask mounted on said base comprising a plate secured on telescoping standards. coiled springs interposed between said plate and the lower parts of the said standards normally urging said plate upwardly, an adjustable releasing means carried by said plate. said operating handle when manually moved downwardly in said guide. serving to place the scaling cap upon said flask and actuating the releasing means. a collar within said cylindei'. a winding drinn. a piston fitting said cylinder and having a piston-band extending through said collar to said drum. a plurality of coiled spring means interposed between said piston and said collar and adapted when under tension and unrestrained to movesaid piston in an upward direction. said piston and piston-band when manually moved downward in the said cylinder serving to place said spring means under tension. lock- `ing means to secure said piston and piston band in opposition to the force of' said spring means. and said piston when released so as to move under the action of said spring means serving to force air through said flexible. conduit and said tube into said flask.I

In testimony whereof I affix my signature in the presence of two witnesses.

SAMUEL J. SYMMUNS.

lVitnesses:

VIOLA C. SYMMoNs, G. W. WIEGAND.

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